The nightmare scenario: a mutating Ebola that spreads easier

The Ebola virus circulating in West Africa is already different from previous strains.

While scientists do not fully understand what the changes mean, some are concerned that alterations in the virus that occur as that pathogen continues to evolve could pose new dangers.

Researchers have identified more than 300 new viral mutations in the latest strain of Ebola, according to research published in the journal Science last month. They are rushing to investigate if this strain of the disease produces higher virus levels - which could increase its infectiousness.

So far, there is no data to indicate that. The risk was that the longer the epidemic went on, the greater the chance the virus could become more transmissible, making it harder to stop, said Charles Chiu, an infectious disease physician at the University of California at San Francisco.

"If the outbreak continues for a prolonged period of time or it becomes endemic, it may mutate into a form that is more virulent. It is really hard to predict."

Viruses such as Ebola are constantly mutating. Some mutations were good for the virus and some were bad for it, said Ian Mackay, a virologist at the University of Queensland. It is the ones that are good for the virus that tend to stick around.